The American Medical Association (AMA) Guides to the Evaluation of Permanent Impairment (Guides) has become the most commonly used source for assessming and rating an individual's permanent impairment in the United States and, increasingly, abroad.

Balancing the tradition of the Guides with the need for a scientific update, the fifth edition of the Guides has retained the focus of earlier editions, while incorporating updates in diagnostic criteria, clarifying key defintions and applications of the Guides, and enhancing readability, accessibility, and consistency.

The updated scientific criteria are a blend of evidence-based medicine and specialty society consensus recommendations.